Government Grants Promoting Cruelty to Animals

Hitoshi Kita -Primate Testing - 2006

Abstract:
The globus pallidus is located at the strategically important locus of
the basal ganglia connections and is considered to play a key role in
the physiology and pathophysiology of the basal ganglia. Our recent
results and those of others suggested that the pallidal neurons change
their firing rate and pattern under various pathophysiological
conditions. One dramatic observation made by us and others was that a
chemical blockade of the subthalamic nucleus (STN) induced a very slow
oscillatory activity, an alternating occurrence of long active and long
silent periods, in pallidal neurons. Our main working hypothesis is that
the slow oscillation of the pallidum might be due to alterations in the
synaptic inputs and the membrane properties of the pallidal neurons. The
goal of proposed study is to characterize the synaptic inputs and the
membrane properties of the pallidum under normal conditions and after
removal of the STN. The whole-cell recording technique in rat brain
slice preparations and the unitary recording combined with local drug
application techniques in awake-monkeys will be used to address the
following two specific aims. Aim-1 will test the hypothesis that
high-frequency unitary activity observed in pallidal neurons in normal
awake-animals is due to the concerted activation of sustained
glutamatergic and sustained GABAergic synaptic inputs. Aim-2 will test
the hypothesis that the removal of the glutamatergic STN-pallidal inputs
alter the firing rate and the pattern of pallidal neurons not only by
the removal of glutamatergic inputs but also by inducing plastic changes
of synaptic inputs and membrane properties. The significance of the
proposed study is that the results obtained will 1) advance our
knowledge of the physiological properties of the pallidum and 2) reveal
changes that might occur in the pallidum of patients suffering from
basal ganglia diseases. These finding might contribute to the formation
of new, less invasive, therapeutic strategies for basal ganglia
diseases.

1Department of Anatomy and
Neurobiology, College of Medicine, University of Tennessee Memphis,
Memphis, Tennessee 38163, and 2Division
of System Neurophysiology, National Institute for Physiological
Sciences, and Department of Physiological Science, The Graduate
University for Advanced Studies, Okazaki 444-8585, Japan

Preparation of animals.
This study was performed in compliance with the National Institutes of
Health Guide for the Care and Use of Laboratory Animals and the National
Institute of Physiological Sciences Guide for the Use and Care of
Laboratory Animals in Research. The monkey preparation methods used in
the present study were very similar to those reported previously (Nambu
et al., 2000 ; Kita et al., 2004 , 2005a ). Each of three Japanese
macaques (Macaca fuscata) was trained to sit quietly in a monkey chair.
Before surgery, each monkey was anesthetized with sodium pentobarbital
(25 mg/kg, i.v.) and ketamine hydrochloride (10 mg/kg, i.m.) and was
placed in a homemade acrylic stereotaxic frame. Then, magnetic resonance
images of the head were taken. The monkeys received surgery to install
headgear for holding their heads painlessly to a metal stereotaxic frame
attached to the chair. Still under the anesthesia, the skull of the
monkey was widely exposed. Small stainless steel screws were attached to
the skull as anchors, and the exposed skull and screws were covered with
acrylic resin. Two stainless steel pipes were mounted in parallel over
the frontal and occipital areas of the skull. The monkey was then
removed from the chair, allowed to recover in the animal housing
facility, and was cared for.

A few days after the initial surgery, a second surgery was performed to
implant stimulus electrodes in the hand region of the primary motor
cortex (M1) and the supplementary motor cortex (SMA). For the second
surgery, the monkey was anesthetized with ketamine hydrochloride (10
mg/kg, i.m.) and xylazine hydrochloride (1–2 mg/kg, i.m.) and was seated
in a monkey chair with its head fixed to a stereotaxic frame. To access
the M1 and SMA, a hole was drilled in the skull. After the monkey
recovered from the anesthesia, and while it was still in the chair, a
glass-coated Elgiloy (Elgin, IL) alloy microelectrode (0.5–1.5 M at 1
kHz) was inserted perpendicularly to the cortical surface. Extracellular
unit activity was recorded in 1–1.5 mm intervals of depth across the M1
and SMA, and the neuronal responses to somatosensory stimuli (skin touch
and passive joint movement) were examined. After extracellular unit
recording, intracortical microstimulation using a train of 12 cathodal
pulses (200 µs duration at 333 Hz) with currents of <50 µA was
delivered, and the movements evoked in the various body parts were
observed.

Rats, mice, birds, amphibians and other animals have
been excluded from coverage by the Animal Welfare Act. Therefore research
facility reports do not include these animals. As a result of this
situation, a blank report, or one with few animals listed, does not mean
that a facility has not performed experiments on non-reportable animals. A
blank form does mean that the facility in question has not used covered
animals (primates, dogs, cats, rabbits, guinea pigs, hamsters, pigs,
sheep, goats, etc.). Rats and mice alone are believed to comprise over 90%
of the animals used in experimentation. Therefore the majority of animals
used at research facilities are not even counted.